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    <title>Document</title>
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    <script>
        //undefined
        //var x;
        //alert(x)
        //字符
        var str1="hello word";
        var str2="hello word";
        console.log(str1);
        console.log(str2);
        //var str3="hello word"
        var str4="小明说；小红很漂亮";
        console.log(str4);
        var set="java";
        //js中先运算等号右边的语句
        str=str+"script";//字符串中+号是链接的意思 javascript
        console.log(str);
    </script>
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